Tumors are relatively common in companion animals (see Mailto and Lagadic (1990) Recueil de Medacine. Veterinaire Special Cancerologie p937-947 for a descriptive epidemiology of canine and feline tumors).
Current methods for treating tumors in cats and dogs include surgery, chemotherapy and radiotherapy. These methods are associated with a number of disadvantages. For example, they all involve a high level of trauma for the patient and they are not always effective in eliminating all the cancerous cells.
An alternative therapeutic approach is immunotherapy which involves the specific or non-specific stimulation of immune reactions of the patient in order to promote the immunological rejection of cancerous cells. There are several methods of immunotherapy:
Non-specific immunotherapy—non-specific stimulation of the immune system (e.g. by using an agent which acts like an adjuvant).
Specific Passive immunotherapy (serotherapy) transferring anti-tumor antibodies to the patient.
Adoptive, immunotherapy—transferring immunocompetent allogenic cells from a healthy individual (eg bone marrow cells)
Specific active immunotherapy—stimulating the immune defenses of the cancer patient by providing the antigens associated with the tumor (e.g. using irradiated cancer cells)
Immunotherapy may be a method of complementary treatment used in combination with surgery, chemotherapy and/or radiotherapy. A study of immunotherapeutic chemical trials in cats and dogs is given in Hayes (1990) Recueil de Medicine Veterinaire 166(11).
An immunotherapeutic approach may be directed against an antigen which is peculiar to the tumor. One strategy for canine and feline cancer immunotherapy would be to identify a tumor-associated antigens (TAAs), expressed on cat or dog tumors, useful for eliciting an anti-tumor immunotherapeutic response.